Wireless communications systems have advanced from simple pager-type systems to integrated voice and data systems. These integrated voice and data systems originally provided text messaging between mobile stations using short message service (SMS). SMS messages are transmitted using signaling system 7 (SS7) within the Global System for Mobile Communications (GSM) mobile application part (MAP) framework, and therefore are limited to 140 bytes.
As the processing power of mobile stations increased there was a desire to send messages that are longer than 140 bytes and include images, audio and/or video. To address this need the 3rd Generation Partnership Project (3GPP) standardized multimedia messaging (MMS), which has been adopted by the Open Mobile Alliance (OMA). Due to the potential for large-sized messages, this standard defined a three step process for delivery of MMS messages, which is illustrated in FIG. 1. After receiving an MMS message from message initiator 105, MMS center (MMS-C) 110 sends an MMS notification message to the intended recipient 120 via push gateway 115. Intended recipient 120 replies with a MMS retrieval request message, and then MMS-C 110 sends the MMS message to intended recipient 120. In addition to being able to exchange larger messages than with SMS, MMS is designed to work in internet protocol (IP) networks. It is envisioned that the next generation wireless networks will include an all-IP core network.